Prosthetic penile implants have been used for many years to allow men suffering from impotence to achieve erection. Some penile prostheses have one or more cylinders with chambers that can be inflatable and may be connected to a fluid-filled reservoir via a pump and valve assembly. Typically, the cylinders of such a prosthetic device are implanted into the corpus cavernosae, the reservoir is implanted in the abdomen, and the pump is implanted in the scrotum. During use, the patient can actuate the pump so that fluid is transferred from the reservoir into the cylinders, producing enough rigidity for an erection. To deflate the cylinders and return the penis to a flaccid state, the patient can actuate a valve assembly within the pump so that the fluid in the cylinders is returned to the reservoir. Some penile prostheses include two cylinders that each have an inflatable chamber for disposal within the distal corpus cavernosae and a rear tip for disposal within the proximal corpus cavernosae toward the pubic bone. During use, the chambers are inflated, but the rear tips are not.
Surgery generally is required to implant a penile prosthesis within a patient. To implant a prosthesis, a surgeon typically makes an incision at the base of the penis and dilates each corpus cavernosum to create space for the cylinders. The distal end of the cylinder (the inflatable chamber) is then inserted into the corpus cavernosum, and the proximal end of the cylinder (the rear tip) is inserted into the body toward the pubic bone (e.g., inserted in the crus). To achieve a proper fit, the surgeon may attach one or more rear tip extenders (RTEs) onto the rear tip of the cylinder. An extender may be in the form of cap (e.g., a silicone rubber cap) that fits onto the rear tip to extend the length of the cylinder to a suitable amount. In some cases, more than one RTE is attached to the rear tip. Typically, these RTEs are attached to the rear tip and to each other via friction fits and/or mechanical interference, and separation of the components is inhibited by a vacuum that results when they are pulled in opposite directions.